The Moons of the Planets

Exercise C4: The Moons of the Planets

Student name: ______Class: ______Date: ______

Check the box with the correct answer.

Question 1: What factor, more than any other, do you think led to Jupiter having so many moons compared to the inner terrestrial planets?

a. The Sun is far enough away from Jupiter that its heat is insufficient to melt icy particles

orbiting the planet; these particles coalesced to form moons.

b. Jupiter's rapid rotation was important in spinning off most of these moons from its

surface.

c. Jupiter has an extensive atmosphere from which these moons have been formed.

d. The powerful gravitational field produced by Jupiter's large mass has allowed this

planet to capture moons from the nearby asteroid belt.

Question 2: The Galilean satellites, in order of decreasing diameter, are:

b. Ganymede, Io, Callisto, Europa

c. Europa, Io, Callisto, Ganymede

d. Io, Europa, Callisto, Ganymede

Question 3: Mercury has a diameter of 4,800 km. Which of the Galilean moons of Jupiter is larger than Mercury?

a. Io

b. Europa

c. Callisto

d. Ganymede

Starry Night College Version 7 1 Question 4: Which factor or factors, more than any other, have allowed Titan to retain an atmosphere?

a. Its many active volcanoes continuously replenish the atmosphere with gas, which is

continuously escaping into space.

b. The molecular constituents of its atmosphere are heavy and cannot therefore escape

Titan's gravity

c. Its surface temperature is too low to allow the nitrogen gas in its atmosphere to escape

from Titan's gravitational force.

d. Its gravitational force has allowed it to acquire atmospheric gases from Saturn.

Question 5: Phobos and Deimos most closely resemble:

c. Planets

d. Dwarf planets

Starry Night College Version 7 2